Circuit card guide

Abstract

A card guide for positioning a circuit card relative to a backplane is disclosed. The card guide provides electrical contacts to a ground plane on the circuit card in addition to positioning the card. The card guide utilizes two types of protuberances to reduce the force needed when the card is inserted or removed from the card guide, while providing accurate mating of paired connectors.

What is claimed is: 
     
       1. A card guide for positioning a circuit card, said circuit card engaging said card guide along an edge thereof, said edge having a predetermined thickness, said card guide comprising: means for defining a first channel having left and right walls and a width greater than said predetermined thickness;   a plurality of first resilient protuberances positioned along at least one of said left and right walls, said first protuberances defining a second channel having a width substantially equal to said predetermined thickness; and   a second resilient electrically conducting protuberance positioned along one of said left and right walls, said second protuberance being positioned such that said protuberance is forced toward said wall on which said protuberance is positioned when said circuit card is inserted into said card guide.   
     
     
       2. The card guide of claim 1 wherein said first protuberances are positioned in opposing pairs, one member of each said pair being positioned on said right wall and the other member of each said pair being positioned on said left wall. 
     
     
       3. The card guide of claim 2 wherein said first protuberances comprise metallic springs having first spring constants, the distance between the members of said opposing pairs being substantially equal to the thickness of said circuit card. 
     
     
       4. The card guide of claim 3 wherein said second protuberance comprises a metallic spring having spring constant less than said spring constants of said first protuberances and being positioned such that said metallic spring engages said circuit card with a predetermined force when said circuit card is inserted in said card guide.